Minnesota officials are trying a novel tactic to block online gambling sites — using a federal law that enables restrictions on phone calls used for wagering.

The state’s Department of Public Safety said last week it had asked 11 Internet service providers to block access to 200 online gambling sites.

The state is citing a federal law that requires “common carriers,” a term that mainly applies to phone companies, to comply with requests that they block telecommunications services used for gambling.

But Internet service providers are not common carriers, meaning it’s unlikely that a court would compel an ISP to comply with Minnesota’s request, said John Morris, general counsel at the Center for Democracy and Technology in Washington.

Morris also noted that the law appears to apply to phone companies directly doing business with bet-takers. But online gambling is already illegal in the United States, so gambling sites are based overseas and U.S. ISPs have no direct links to them.

“I think this is a very problematic and significant misreading of the statute,” Morris said.

In a similar case, Pennsylvania briefly imposed requirements for ISPs to block child-pornography sites. But a federal court struck down the law in 2004 because the filters also blocked legitimate sites.

John Willems, director of the Alcohol and Gambling Enforcement Division of Minnesota’s Department of Public Safety, said that since telecommunications companies now provide more than just phone service, the requests “seem to be a reasonable application of the law.”

“We’ll see how the conversation unfolds from there,” he said.

AT&T, which received one of the requests, said it was reviewing it. Comcast and Qwest Communications International, which also received requests, had no immediate comment.

John Palfrey, codirector of the Berkman Center for Internet & Society at Harvard University, said the idea of forcing Internet service providers to filter sites almost has been abandoned because it works so poorly. Either too many sites are blocked, or too few — meaning that even if the ISPs were to cooperate, online gamblers might get around the filters by finding sites that aren’t on the list.